Central axis water turbines harness power from water currents by using the flow of water to energise the turbines and generate other usable forms of power. The design of central axis water turbines has been influenced by the design of wind turbines which use the flow of air to energise the turbine. The blades of turbines are traditionally straight blades that extend radially outwards, perpendicular to the central axis of the turbine.
While both wind and water turbines generate power from the flow of fluid over the turbine blades, there are significant differences between the characteristics of water flow and air flow through turbines and over the blades.
For these and other reasons, known central axis water turbines do not provide optimum usable power output in typical water flow conditions.
The present invention seeks to ameliorate one or more of the abovementioned disadvantages.